1. Field:
The invention is in the field of musical instruments, specifically pianos and, more specifically, grand pianos. Still more specifically it is in the field of actions for grand pianos, the mechanisms through which a string is struck when a key is depressed.
2. Prior Art:
There is profuse prior art in the specific field of actions for grand pianos. The patents listed below, a sampling of the art, include patents selected as particularly relevant to the subject action.
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A U.S. patent application Ser. No. 104,277, filed 10/02/87, U.S. Pat. No. 4,89 by the subject inventors is also pertinent prior art. However, the most pertinent prior art is the Herz-Erard action which has been in most common use for many years. This action has been and is considered entirely adequate and there has been no well known call or suggestion for improvements in it or for an improved one to supercede it. Nevertheless, certain characteristics of the Herz-Erard action are recognized by those skilled in the art as providing a basis for seeking improvements in the action for grand pianos. The Herz-Erard action is acknowledged to be complex, resulting in considerable cost to manufacture it and in its being relatively difficult and sensitive to adjust. The complexity contributes to its fragility. Further, partly because of the complexity and partly because of the need to use soft cushions in the action, the action must be adjusted frequently to maintain top performance and avoid unwanted noises.
Therefore the prime objective of the subject invention is to provide an action for grand pianos which is improved over the Herz-Erard action with no sacrifice in performance. Further objectives are that the improvements include less complexity, with related lower cost of the action and simplification of adjustment, greater durability, allowance of less frequent adjustment to maintain top performance, and reduction of noises in the action. These mechanical noises are irritating to pianists and a particular problem when the grand piano is being recorded by sensitive high fidelity equipment.